Automotive Air Conditioning Information Forum

I have a 2010 Subaru Forester with 90k miles. AC gets very cold when it works. I re-charged the system after the AC o-rings were replaced 5 months ago. In cool days, AC works for a long time, but in hot days, AC only works for less than 10 minutes. If I turn off AC and wait for a while, AC would work again for a few minutes. The compressor clutch is disengaged when this happens, and there is no current flow to the clutch (measured with a clamp multi-meter).
If I turn on AC blower fan inside the cabin to the highest setting when I start the car, AC clutch runs fine as long as I don’t turn off AC or shut down engine.
I checked the AC low and high pressure lines, the readings were 110 psi when AC not running, and 30~50 for low, 220 for high when clutch engaged.
I scanned the OBD port, and there was no code.
Where should I start? Appreciate your inputs.

I'm not an AC professional, and don't know much about Subarus except that my daughter drives one.

But I think I would test the blower resistor for the blower fan. Since at times you have no positive voltage getting to the AC compressor clutch, sure sounds like an electrical issue as opposed to a compressor issue !

We assume your pressure readings were at 1500 -2000 rpm.

Your hi/lo pressures seem fine if indeed they were at 1500-2000 rpm. I agree with cusser to look for an electrical fault